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Leymus cinereus - basin wildrye

Scientific Family
Poaceae
Synonyms
Elymus cinereus
Other common names
Great Basin wildrye
giant wildrye
Great Basin lyme grass
Plant type
Grasses
Riparian
Yes

Grass Description

Origin
Native
Season
Warm

Grows along streams, gullies, and roadsides, gravelly to sandy areas in sagebrush and open woodlands, moderately dry open places.

Plant Community
Disturbed Areas
Interior Chaparral
Pinyon Juniper Woodlands
Riparian
Grasslands
Low elevation
1950
High elevation
9500

General Description

Robust plants grow in clumps 1 to 3 feet wide, are rhizomatous and usually bright green. Stems are hairy, up to 7 feet tall, 1/4 inch thick and densely arranged. Basin wildrye is the largest cool-season perennial bunchgrass native to the western U.S.

Strongly tufted; seedheads are thick spikes with mostly 2 to 4 spikelets per node; lemmas hairy, awnless or awned tipped, blades 3 to 12 mm wide; culms 70 to 270 cm tall.

Grass type
Perennial bunchgrass
Rhizomes
Yes
Stolons
No
Clump Diameter 2 ft or more
Yes
Bushy - highly branched
No
Height with Seedheads
Greater than 36 inches
Seedhead Structure
Unbranched
Seedhead droops
No
First bloom month
June
Last bloom month
August

Flower Characteristics

Flowers per Spikelet
Multi-flowered
Spikelets One-Sided
No
Awns
Less than 1/4 inch
Three Awns
No
Awns bent
No
Flower and Seedhead Notes

Seedheads 6 to 10 inches long, dense, unbranched cylindrical spike with up to 35 nodes, each node having 2 to 7 spikelets per node, spikelets 3 to 7 flowered.

Vegetative Characteristics

Blade is hairy
No
Blade margins white
No
Blade cross-section
Flat
Involute – rolled inward on upper surface

Basin wildrye has leaf blades 15 to 25 inches long and up to 3/4 inch wide.

Sheath is hairy
Yes
Tufts of hair top of sheath or collar
No
Ligule
Membranous
Auricles
Yes

The early growth and abundant production of basin wildrye make it a valuable source of forage for livestock and wildlife.